Hermetic alkaline storage battery

Abstract

Alkaline storage battery cells having negative electrodes with higher capacity than the positive electrodes. The positive electrodes have discharge limiting capacity. The negative electrodes have additive of Raney metal, or Raney metal alloy. Such cells constituting a battery.

We claim: 
     
       1. In an alkaline storage battery cell which is hermetically sealed, and which includes a negative electrode having higher capacity than the positive electrode, the improvement wherein the positive electrode is constructed and arranged to provide a capacity which is limiting during discharging, and   the negative electrode includes additive selected from the group of reduced Raney metal and Raney metal alloy of one or more metals in Group VIII of the periodic table,   the additive being present in a quantity sufficient to conduct the maximum polarity reversal current.   
     
     
       2. The cell of claim 1 wherein the selected additive includes Raney nickel. 
     
     
       3. The cell of claim 1 wherein the additive is selected from the group of Raney nickel, Raney nickel iron, Raney nickel cobalt, Raney nickel with palladium alloy, and Raney nickel with platinum alloy. 
     
     
       4. The cell of claim 1 wherein the electrodes are substantially free of anitpolar mass. 
     
     
       5. The cell of claim 1 wherein the additive is present in an amount greater than about 0.25 grams/ampere of polarity reversal current. 
     
     
       6. The cell of claim 1 wherein the negative electrode also includes a hydrophobic medium. 
     
     
       7. The cell of claim 1 which has nickel and cadmium electrodes. 
     
     
       8. The cell of claim 1 which has nickel and iron electrodes. 
     
     
       9. A battery formed of a plurality of cells according to claim 1. 
     
     
       10. The cell of claim 4 which is assembled by a process comprising the steps of introducing the positive electrode in substantially discharged condition, and introducing the negative electrode with oxidized Raney nickel and oxidized cadmium. 
     
     
       11. The cell of claim 2 which is assembled by a process comprising the steps of introducing the positive electrode in substantially charged condition and the negative electrode in substantially reduced condition. 
     
     
       12. The cell of claim 5 wherein the additive is present in an amount of about 1 gram/ampere. 
     
     
       13. The cell of claim 10 wherein the negative electrode introduced in the assembly process further contains unoxidized cadmium. 
     
     
       14. The cell of claim 13 whose assembly process comprises the further step of charging at elevated temepratures. 
     
     
       15. The cell of claim 11 whose assembly process comprises the further step of removing hydrogen from the negative electrode by exposing said electrode to an alkaline medium at temperatures above about 40° C. 
     
     
       16. In the method of producing an alkaline storage battery cell which is hermetically sealed, which includes a negative electrode having higher capacity than the positive electrode and which is subject to polarity reversal during deep discharging the improvement which comprises the step of   incorporating in the negative electrode additive selected from the group of reduced Raney metal and Raney metal alloy of one or more metals in Group VIII of the periodic table in a quantity sufficient to conduct the maximum polarity reversal current.   
     
     
       17. The method of claim 16 wherein the additive is incorporated in a quantity sufficient to conduct the maximum polarity reversal current. 
     
     
       18. The method of claim 16 wherein the electrodes are formed substantially free of antipolar mass. 
     
     
       19. The method of claim 16 further comprising the steps of introducing the positive electrode into the cell in substantially discharged condition, and introducing the negative electrode with oxidized Raney nickel and oxidized cadmium. 
     
     
       20. The method of claim 16 further comprising charging the cell at elevated temperatures. 
     
     
       21. The method of claim 16 wherein the positive electrode is introduced into the cell in substantially charged condition and the negative electrode in substantially reduced condition. 
     
     
       22. The method of claim 16 further comprising the step of removing hydrogen from the negative electrode by exposing said electrode to an alkaline medium at temperatures above about 40° C. 
     
     
       23. The method of claim 19 further comprising incorporating unoxidized cadmium into the negative electrode.